what to choose for backup: HDD or DVD

Question

I want to backup my photos and I would like to know which is the better media to store them. I would prefer to store them on an HDD because of the space, but I don't know who has a better lifetime.

Answer 1

I don't have a specific set of results to link to but generally DVDs are considered to be a poor long term storage medium when compared to a HDD due to the instance of errors and degrading of the DVDs over time.

I would also say to store them on multiple HDDs so you have a redundant backup, keep a HDD in your desk drawer at work and also have one at home and you should be pretty well covered.

If you were concerned about having an unencrypted hard drive at work (or anywhere else) you could use TrueCrypt to encrypt these external HDDs, meaning that you would have to mount them using the TrueCrypt software and enter a password before using them.

Answer 2

Unfortunately none of us can give you a single answer, so instead, i'll be giving you info to help you decide better.

Lifetime:

HDDs tend to live longer than DVD-Rs given the same amount of effort in storage care.

According to the Optical Storage Technology Association (OSTA), "manufacturers claim life spans ranging from 30 to 100 years for DVD, DVD-R and DVD+R discs and up to 30 years for DVD-RW, DVD+RW and DVD-RAM".✝

HDDs last 5-10 under casual use and up to 300 years in good storage.

There are also expensive data recovery services out there and it seems that recovering from HDs is cheaper than any other service they offer.

Practicality:

A 500gb HD is equivalent to around 107 4.7gb DVDs. The HDD would take up less physical storage space even with redundant backups.

around 20 years from now it's safe to assume that 4.7gb DVDs would get outdated (This is personal opinion only) while sata HDDs might not. That would mean along with your DVDs you'd also have to keep a working DVD reader for future use.

If ever the media you choose does get outdated it would be easier to transfer files between HDs than a bunch of discs.

Reliability:

Because HDDs have a lot more storage space, that would mean more stuff would be lost in one case of failure. Losing an HD would mean losing 500gb worth of data while losing a DVD would mean losing 4.7gb of data. But this should be negligible with redundant backups and also because HDDs last longer than DVDs

Price:

with equivalent data storage, DVDs are cheaper per gig than HDs. But personally i think if you're keeping precious memories price should matter the least.